Grown up out of the Spy Kids franchise, awkwardly charming Alexa Vega has run smack into tweens heck. Less obviously self-absorbed than her slight elders Lindsay Lohan, Hilary Duff, or Mary-Kate and Ashley, she's still cute like a child, not nearly so jailbaity as the current fashion. At the same time, she can pass for clever, so you can imagine her on her way to full-fledged adolescence, eager, smart, and appropriately poised.

In the doggedly unoriginal Sleepover, Vega carries a heavy load with impressive grace. As Julie, just graduating from junior high school, she faces the imminent loss of her best friend, Hannah (Mika Boorem), whose family is moving away. In an effort to ease the parting and look forward to the next stages of their lives, the girls plan a slumber party, despite (or because of) the fact that Julie's mom, Gabby (Jane Lynch), has forbidden her from leaving the house.

As if to raise the nominal stakes for the girls' last night together, the overwrought film (written by Elisa Bell and directed by Joe Nussbaum) puts them in a humdrum predicament. They back into a competition with the popular (mean) girls for the best lunch spot at high school (which won't start for three months, and which, one would think, already has a system in place for assigning lunch tables). The contest involves a scavenger hunt, pitting Julie and nice girls Hannah, Yancy (Kallie Flynn Childress), and Farrah (Scout Taylor-Compton), against Staci (Sara Paxton) and her self-absorbed, already Barbicized compatriots. Sure that they'll win the scavenger hunt, the popular girls also plan to make it to the graduation dance in time to show off to everyone their consummate superiority.

The night is reduced to a series of episodic shenanigans. First, Julie and Hannah must secure the help of Julie's brother Ren (Sam Huntington), to distract their goofy, supposedly babysitting dad Jay (Jeff Garlin) while the girls sneak out the window. The evolving scheme involves Ren feigning interest in Jay's monumental efforts to install a water purifier in the kitchen sink, making noises like the girls dancing upstairs (to the Spice Girls' "Wannabe" -- um, isn't this 2004?), and chowing down the pizzas the girls have ordered before their departure (the gluttony leads to bloated bellies for him and the family dog -- not exactly hilarious, but not quite fart jokes either).

The scavenger tasks include Julie's posing as an "older" girl to meet an online-organized date, which means that while her friends wear their own clothes, she's decked out in her mom's red dress, made vaguely sensational by some crafty cutting (this makes for a nifty visual when, pressed for time, Julie takes off on a skateboard, scooting through suburban streets, her dress splashy in car headlights). The fact that she has arranged to rendezvous with the girls' teacher, Mr. Chilton (Timothy Dowling), is not a little disturbing (what is he doing trolling the internet for dates?). The awkward moment is somewhat ameliorated by the turn of events: Hannah and Julie encourage him to take off his glasses and muss his hair to attract a woman his own age. (Thanks, girls!)

For the most part, however, it is the girls and not adults who must learn lessons throughout the movie's inelegant installment structure. They are hounded by a relentless neighborhood security officer named Sherman (Steve Carell, who is plainly typecast for life), determined to prove something by capturing them and obviously incapable of learning anything. They also end up ducking Julie's mom, who inconveniently (or conveniently) shows up dancing at the same club where the girls meet Mr. Chilton. (What is it with the adults in this town, anyway?)

On the boys front -- which is, after all, the front that matters most for 14-year-old girls raised on mass media -- Julie has fallen hard for a cute high school jock named Steve (Sean Faris). And, lucky her, the scavenger hunt demands that she get hold of a pair of his precious boxers. Inverting the Rapunzel plot, maybe, Julie indulges in some minor breaking and entering to accomplish her goal, whereupon she catches a glimpse of Steve preparing to shower. Focused on her appreciative look, the scene avoids showing what she sees, in accord with Sleepover's consistent attention to her desire and her energy.

In this context, the parents, the boys, and the rivals all serve one function, to showcase Julie's evolution during this special, if ridiculous, night. As a girls' movie, Sleepover is most effective when it focuses on Julie and Hannah's complex and recognizable friendship, in the throes of difficult change. But the movie is also relentlessly predictable. How about a girls' plot that doesn't include a dance, fancy dress and crown, and a kiss with Prince Charming?

There's a rotten core at the center of Lubitsch's Heaven Can Wait. No matter how engaging I find Haskell and Sariss's enchantment with the film, I cannot accede to their critical adulation of it and of Henry.

In the Coen Brothers' The Ballad of Buster Scruggs, there's something altogether new about having revisionist western ideas filtered through their rich sense of character, black comedy, and their penetrating awareness of humanity's fatal imperfections.